This is the beginning of the end for a lot of textbook stores nationwide, especially once Amazon's full-color tablet comes out this fall:

Today, Amazon announced a new Kindle textbook rental program that allows students to rent digital textbooks from the Kindle Store for super cheap.

Textbooks can be rented for any amount of time between 30 and 360 days.

If you rent for 30 days (if you're taking a mini-course or something of that sort), you can save up to 80% off the textbook list price by renting.

Amazon's announcement is here. This is going to be a big problem for Barnes & Noble, who operate over 600 campus bookstores around the country.